bug-58 Card UI:

1. Include genzeb's filp library to create 3D filp view.
2. Include Picasso library for download and caching images.
3. Link to Wikipeddia.
3. Use icomoon font on previous and next button.
4. When it can't display card content correctly, show error card UI. 

This is an old warning. There are 3 candidates to eliminate it: 1. put 0/0 to string.xml, 2. initialize the 0/0 in the code, and 3 just remove the `text` attribute.